1. Field of the Invention
This invention relates to an apparatus for directing the flow of material, such as particulate material, and, more particularly, for emptying the contents of silos.
2. Description of Background and Relevant Materials
Various types of devices for emptying the contents of silos are known in the art. One of these is shown in European Patent 84 750, filed Dec. 17, 1982, also in the name of Applicant herein.
The apparatus which is the subject of this European patent comprises a plurality of hollow ribs situated at the bottom of a silo. These ribs have sides which form the hoppers of the apparatus; they are connected by perforated plates forming the ends of these hoppers.
Each rib has orifices opening under the perforated plates. Means are provided for sending pressurized air into the channel formed by the ribs.
This apparatus increases the flow rate of the material being emptied from the silo. However, since the ribs forming the visible bottom of the silo are subjected to very substantial pressures, they must be constructed from corrugated and arched sheet iron. Consequently, using such ribs, it is difficult to achieve an airtight seal at both the bottom of the silo and the perforated plates. These problems can be overcome, but at a substantial increase in the cost of installation.